Oil and Natural Gas Property Transactions - Narrative (Details) shares in Millions, $ in Millions		2 Months Ended	3 Months Ended				5 Months Ended	6 Months Ended
	Feb. 01, 2019 USD ($) shares	Mar. 31, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($) well		Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($) a well
Business Acquisition [Line Items]
Revenues			$ 2,386		$ 2,289	[1]		$ 4,582	$ 4,813	[1]
Proceeds from divestitures of proved and unproved properties								82	384	[2]
Mid-Continent
Business Acquisition [Line Items]
Proceeds from divestitures of proved and unproved properties									$ 491
Number of net acres | a									238,500
Productive gas wells, number of wells, net | well					3,200				3,200
Other properties
Business Acquisition [Line Items]
Proceeds from divestitures of proved and unproved properties			$ 56	$ 5				$ 82	$ 23
Wildhorse Resource Development Corporation
Business Acquisition [Line Items]
Common stock issued in the merger (in shares) | shares	717.4
Cash	$ 381
Revenues							$ 308
Operating expenses		$ 369
Other expenses		$ 54

[1] Financial information for 2018 has been recast to reflect the retrospective application of the successful efforts method of accounting. See Note 1.

[2] Financial information for 2018 has been recast to reflect the retrospective application of the successful efforts method of accounting. See Note 1.